1. Field of the Invention
This invention relates to countertops manufactured of solid surfacing material generally of thick non-laminated rigid plastics. More particularly this invention pertains to the defining of a countertop utilizing adhesively seamed modular panel sections of polymeric solid surfacing material.
2. Description of the Related Prior Art
Countertops made of solid thick plastics, that is, non-laminated plastic solid surfacing material have become quite popular in kitchens, bathrooms, and offices. The growing popularity of plastic solid surfacing materials to define countertops is due to the material having the qualities of high durability and ease of damage repair, ease of cleaning and sterilization, and beauty. Another widely appreciated aspect of plastic solid surface countertops is the appearance of a single and continuous countertop even when it is fabricated of many adhesively bonded sections.
Solid surfacing materials as referred to in this disclosure are non-foamed, non-laminated polymer based materials in relatively thick rigid sheet form useful for defining surfaces. Plastic solid surfacing materials are most often manufactured and sold in sheet form, typically in 30 inch wide .times. 12 foot lengths in thicknesses between 1/4 through 3/4 inches. Such polymer based solid surfacing materials are typically manufactured substantially of polyester or acrylic resins, or alloys thereof, depending upon the manufacturer and the particular formula being used, and most often contain various quantities of other components or additives both natural and synthetic to form desired color, visual patterns, and other desirable visual and physical characteristics.
Plastic solid surfacing materials are available from several U.S. manufacturers such as E. I. dupont de Nemours & Co., Inc. of Wilmington, Del. 19898 U.S.A., who market their polymer based solid surfacing materials under the trademark of "Corian". "Corian" is a trademark of Du Pont which refers to their solid surfacing polymer based material. "Corian" is a substantially rigid, non-foamed, non-laminated, non-coated solid material composed primarily of acrylic components, and containing smaller quantities of additives. "Corian" is most often made and sold in sheet form. U.S. Pat. No. 3,847,865 issued Nov. 12, 1974 to R. B. Duggins and assigned to E. I. duPont de Nemours & Co., teaches one formula for making plastic solid surfacing material of the general nature of that referred to in this disclosure.
Another manufacturer of polymer based solid surfacing material is the Nevamar Corporation located at 8339 Telegraph Rd., Odenton, Md. 21113 U.S.A. The Nevamar Corporation markets their solid surfacing material under the trademark of "Fountainhead". "Fountainhead" is a substantially rigid, non-foamed, non-laminated, non-coated solid material composed of a polymer alloy comprised mostly of polyester components having therein various percentages of acrylic components. "Fountainhead" is most often made and sold in sheet form.
Another manufacturer of polymer based solid surfacing material is the Formica Corporation, located at 155-T Rte. 46, W., CN-980, Wayne, N.J. 07470 U.S.A. The Formica Corporation sells their solid surfacing material under the trademark name of "Surell". "Surell" like "Corian" and "Fountainhead", is a dense solid plastic most often made and sold in sheet form. "Surell" is a substantially rigid, non-foamed, non-laminated, non-coated solid material composed substantially of polyester components.
Du Pont, the Nevamar Corporation, and the Formica Corporation, and several other companies not specifically herein mentioned, who produce very similar polymer based solid surfacing materials to one another, manufacture and sell polymer based solid surfacing materials in sheet form intended for use as vertical walling or horizontal countertops.
Some additional recognized advantages of using polymer based solid surfacing materials such as "Corian", "Fountainhead" or "Surell" over other available materials such as wood, metal, ceramic tile, and high pressure plastic laminates for countertops, exists in the fact that the material is a solid, polymeric non-laminated structure which the color or decorative color patterns extend deep or completely therethrough. If polymer based solid surfacing material does become stained, burned or scratched so deeply that the damage cannot be removed with a common household cleanser, the damage can be easily removed by light sanding with steel wool or fine sand paper, and this due to the fact that the material is solid, and the color or visual patterns extend generally completely therethrough. Furthermore, plastic solid surfacing materials typically have a high tensile strength, are hard, dense and rigid, and are resistant to chipping, splitting, warping, burning, and staining, all of which cannot be said about the many other materials which could and have been be used to define countertops. Another attractive quality associated with polymer based solid surfacing materials is the availability of properly colored adhesives for permanently gluing pieces of the material together. Additionally, the polymer based sheets can be cut to size or otherwise shaped with mechanical material removal methods and tools using sawing and shaping tools such as router bits, power saws and shapers and the like, similar to those used to cut and shape wood.
Polymer based solid surfacing materials such as "Corian", "Surell" or "Fountainhead" may be manufactured at a relatively low price to very closely resemble the texture and appearance of marble, granite, and other natural stone products which have long been desired and used as building materials due to recognition of the durability and beauty of such natural substances. It should be noted that not all plastic solid surfacing material is colored to simulate a stone product. Although plastic solid surfacing material is usually less expensive to purchase than natural stone for use as a countertop, plastic solid surfacing material is still, at least in the short term, relatively expensive compared to high pressure laminates commonly used for countertops. Due to the relative high material cost coupled with the current level of required skill in properly installing plastic solid surfacing material, mostly in the cutting and seaming thereof to achieve flat surfaces and strong imperceptible seams, and thus the desired single piece construction appearance, solid surfacing countertop material is normally not sold directly to the general public, but instead is sold to highly trained and usually factory certified professional installers who will properly cut and seam the material in the customers home or office. "Professional installer" or "professional" will henceforth generally refer to one who is highly skilled and practiced (experienced) in properly installing plastic solid surfacing material, and who installs such material usually on a daily basis as a profession.
Common prior art techniques employed by professional installers of plastic solid surface countertop include applying interlocking grooved or otherwise registerable side edges on the sides of two large panels of the material to be adhesively joined. These registerable edges are typically applied in the field utilizing a router and a readily available cutting bit which makes registerable or matable serrations. The registration of the edges is important for achieving matching levels on the adjacent top or upper surfaces of two large flat horizontal panels being joined. Proper registration of the top surfaces of two adjacent panels is critical in terms of reducing finishing sanding to a minimum and in achieving a substantially flat overall countertop surface. Additionally, it is very common for sheets of solid surfacing material to vary in thickness, up to 0.055 from one sheet to the next from the same manufacturer, even though they are of the same nominal thickness. This variation of sheet thickness results in the tops of two adjacent sections of different thickness being misaligned when the two sections are placed side-by-side resting atop a flat support surface, therefore interlocking registration structure is usually needed and applied when large flat sections or panels of plastic solid surfacing materials are adhered to one another to define a single large flat countertop section. The registration of the two adjacent side edges is applied to align the adjacent top surfaces, and this of course leaves the underside surfaces slightly misaligned or laying in different planes to the degree in which the two panels vary in thickness, which does not create any significant problems due to the small degree of typical thickness variations.
Another typical procedure utilized by professional installers is to apply clamping pressures to draw seams together during the joining process wherein the proper color of liquid adhesive which sets by catalytic action is used to permanently connect two pieces. Such clamping is of importance in consistently achieving both a strong and properly aligned joint, and a finished joint which will be imperceptible when completed. Typically, professional installers either use commercially available set-screw clamps, or spring biased squeeze clamps commonly called "pony clamps" to apply clamping pressures to joints during the adhering process. The set-screw type clamps are typically of the long bar type capable of spanning across two wide or long panels being joined. The professional installer, being a highly skilled craftsman in his art knows from experience the proper initial clamping pressure to apply to the joint being glued. With set-screw clamps, the professional can set the proper initial clamping pressure utilizing feel and by visually watching the adhesive flow upward out of the joint. He also knows that with the use of set-screw clamps, that as the quick-setting adhesive flows out of the joint, with the passage of several minutes and prior to the adhesive fully curing, that he must repeatedly re-tighten the set-screw clamps the proper amount in order to again properly close the joint and to compensate for the adhesive having moved out of the joint during the hardening process after the initial setting of the clamping pressure. Due to this re-tightening requirement with the use of set-screw type clamps, professional installers often prefer to use spring clamps (pony clamps) whenever possible, since the spring clamps have the distinct advantage of continuously working utilizing their inherent spring loading to close the joint as the adhesive flows during the hardening process. Thus, once a spring biased clamp is properly set to close a joint in the process of being glued, the spring clamp need not be again adjusted since it is self adjusting by the nature of the loaded spring, but remains in place until the adhesive has hardened.
The spring clamps typically only open at the jaw about 3to 4 inches, being pivotally hinged between the handle end and the openable jaw end, and thus, professional installers utilizing spring clamps temporarily affix blocks of plastics or other materials using hot melt glue on the top surface on each side of the joint, and then apply the spring clamps spanning across the temporary blocks to draw the joint together. After the adhesive in the joint has fully set, the blocks applied for the spring clamp must then be removed. With spring clamps, the professional installer knows from experience the approximate strength of the spring clamping pressures, he knows how many clamps to use and where to place the clamps, and he also knows where to attach the temporary blocks, since placing the blocks nearer or farther from the joint and one another will effect the clamping pressure applied to the joint when using spring clamps. The clamping pressures are relatively critical, in that insufficient pressure can lead to a weak joint and unsightly voids and gaps in the finished joint, and too much clamping pressure squeezes an excessive amount of the liquid adhesive out of the joint to leave insufficient adhesive to render an adequately strong joint, leading to "dry joint failure" as it is referred to in the industry.
Other prior art which is known to us and believed somewhat pertinent to the present invention is in U.S. Pat. No. 5,253,932 issued Oct. 19, 1993 to D. N. Nesovic for "Modular Countertop System"; and also in U.S. Pat. No. 5,018,628 issued May 28, 1991 to R. Schenck et al for "Working Surface". The Nesovic patent teaches a modular countertop system which may utilize plastic solid surfacing material, and utilizes numerous smaller pieces to define a finished larger countertop. Nesovic indicates pins or dowels inserted into holes may be used for alignment and registration purposes, and for these reasons the Nesovic disclosure is relevant to the present invention, although it does not teach or anticipate the present invention. The Schenck et al disclosure is believed relevant because it teaches a modular countertop defined by components which may be releasibly joined utilizing a tongue and groove interlocking arrangement which also gives registration. The Schenck et al disclosure however does not teach or anticipate the present invention.
Other prior art related to countertops of which we are aware is shown in U.S. Pat. Nos. 3,606,508; 2,895,778; 2,038,638; 2,970,872; and 2,614,014. These patents teach countertop construction in various manners and are therefore related to the present invention, although they do not teach or suggest the present invention or solve the problems solved by the present invention.
It is believed that the providing of an error resistant arrangement wherein a non-professional having little or no experience in this particular field could easily join sections of plastic solid surfacing material together to define a countertop would be a significant improvement in the art, and would be to the benefit of both the general public and to manufacturers of plastic solid surfacing materials. Such a feasible modular countertop using plastic solid surfacing material would be inherently simple and error resistant to install so as to allow the "amateur" (not a factory trained or highly experienced professional) to properly install his own countertop and save a substantial amount of money on hired labor. Such a modular countertop would necessarily incorporate methods and structures to help insure that any connected seams defined by the amateur installer would be strong and virtually imperceptible when completed, since one of the widely appreciated and sought after aspects of plastic solid surface countertops is the appearance of a single and continuous countertop even when it is actually fabricated of many adhesively bonded sections. Such a feasible modular countertop arrangement would need to provide both error resistant panel registration and clamping to allow the inexperienced installer to permanently seam components of the modular countertop together, and hopefully with the end results appearing quite professional. Additionally, such a modular countertop would require not only minimal skills of the inexperienced installer, but ideally would require few specialty tools, with this being to further hold the cost of installation to a minimum.